Try this simple tip on your serve.
Importance of the ball release.
Practice all the time even when your not serving.
You can do this drill with a partner. Throw the Ball to your partner with the ball toss method. Keep a straight arm with a smooth Action. Release the ball out in front of your body. Getting the ball high above your head is crucial. Having a low ball toss will cause problems with your contact point.
See picture below.
I am practicing my boss release. If you Have 10 spare min just go and practice.
Coming up this week
Serving ball release tips
Photos
Videos 
Simon 'H' Tennis 